Once the weather begins to cool off, you may be concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely add up to a large chunk of your monthly electric bill. To try and find ways to save, some homeowners look closely at their thermostat. Is there a setting they could use to improve efficiency?
Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what does the fan setting provide for your HVAC system? This guide can help. We’ll review just what the fan setting is and when you can use it to save money over the summer or winter.
What Is the Fan Setting on My Thermostat?
For the majority of thermostats, the fan setting signifies that the air handler’s blower fan keeps running. Some furnaces will operate at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start the fan over a heating or cooling cycle and switch it off after the cycle is complete.
There are advantages and disadvantages to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your distinct comfort requirements.
Advantages to trying the Fan/On setting:
- You can keep the temperature in each room more consistent by allowing the fan to keep circulating air.
- Indoor air quality will be highest as constant airflow will keep passing airborne particles through the air filter.
- A smaller amount of start-stop cycles for the HVAC fan helps expand its life span. Since the air handler is often a component of the furnace, this means you might minimize the risk of needing furnace repair.
Downsides to using the Fan/On setting:
- A constant fan could raise your energy costs slightly.
- Continuous airflow may clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air can linger in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system may draw this warm air into the rest of your home, pushing the HVAC system to run longer to keep up with the set temperature. In extreme heat, this may lead to needing AC repair more often as wear and tear grows.
The opposite can happen during the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually drift into the rest of your home. Leaving the fan running may pump more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may work for you if:
Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be tough on the family. Leaving the fan on should help to enhance indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Many homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help lessen these changes by steadily refreshing each room’s ventilation.